维生素D对羊膜腔注射脂多糖导致的新生鼠肺泡化阻滞的作用
Effects of Vitamin D on intra-amniotic lipopolysaccharides-induced alveolarization arrest in neonatal rats

目的 探讨维生素D（VitD）对宫内绒毛膜羊膜炎诱发的肺泡化阻滞的改善作用及可能的机制。方法 通过孕鼠羊膜腔注射脂多糖（LPS）建立新生鼠支气管肺发育不良（BPD）模型。分为Saline组、LPS+Saline组、LPS+VitD（L）组和LPS+VitD（H）组。VitD干预的2组新生鼠出生后每日腹腔注射0.5和3 ng/g的1, 25(OH)2D3，Saline组和LPS+Saline组注射等量生理盐水。取第1、3、7日的新生鼠肺组织，通过苏木精-伊红（H-E）染色观察病理学改变。采用real-time PCR检测IL-1β和IFN-γ mRNA表达。结果 不同剂量的VitD均显著提高新生鼠出生率（均P=0.003）。出生后7 d，VitD干预的2组较LPS+Saline组肺泡计数显著增多（P=0.001，P=0.000），平均内衬间隔显著减少（均P =0.000），且VitD干预的2组IL-1β和IFN-γ mRNA表达显著低于LPS+Saline组（均P=0.000）。结论 予以VitD可降低新生鼠肺部IL-1β和IFN-γ表达，减轻BPD病理学改变。
： Objective To investigate the role of Vitamin D (VitD) on amelioration of chorioamnionitis-induced alveolarization arrest and possible mechanisms. Methods A neonatal rat bronchopulmonary dysplasia (BPD) model was constructed by intra-amniotic injection of lipopolysaccharides (LPS) in pregnant rats. Rats were randomly assigned to the Saline group, LPS+Saline group，LPS+VitD (L) group, and LPS+VitD (H) group. Neonatal rats in the LPS+VitD (L) group and the LPS+VitD (H) group were intraperitoneally injected with 0.5 and 3 ng/g 1, 25(OH)2D3 respectively once a day for 7 d. Meanwhile, neonatal rats in the Saline group and the LPS+Saline group were intraperitoneally injected with the same volume of normal saline. The pulmonary tissues of neonatal rats were harvested 1, 3, and 7 d after the final injection and were stained by H-E staining for observing pathological changes. The mRNA expressions of IL-1β and IFN-γ were detected using real-time PCR. Results Different concentrations of VitD could improve the birth rate of neonatal rats (P=0.003). The LPS+VitD (L) group and the LPS+VitD (H) group had significantly higher alveolar counts (P=0.001, P=0.000), remarkably decreased mean liner intercept (P=0.000), and significantly decreased mRNA expressions of IL-1β and IFN-γ as compared with the LPS+Saline group 7 d after birth (P=0.000). Conclusion Administration of VitD can significantly decrease the expressions of IL-1β and IFN-γ in lungs of neonatal rats and alleviate the pathological changes of BPD